How severe is CVE-2025-24839?

CVE-2025-24839 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2025-24839 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-24839?

CVE-2025-24839 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-24839?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-24839 have an EU (EUVD) identifier?

Yes. CVE-2025-24839 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11360.

When was CVE-2025-24839 published?

CVE-2025-24839 was published on 2025-04-16 and last updated on 2026-06-17.

CVE-2025-24839

CVE-2025-24839 is a low-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 3.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-863.

Key facts

Severity: Low (CVSS 3.x base score 3.1)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11360
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2025-04-16
Last modified: 2026-06-17

Description

Mattermost versions 10.5.x <= 10.5.1, 10.4.x <= 10.4.3, 9.11.x <= 9.11.9 fail to prevent Wrangler posts from triggering AI responses. This vulnerability allows users without access to the AI bot to activate it by attaching the activate_ai override property to a post via the Wrangler plugin, provided both the AI and Wrangler plugins are enabled.

Frequently asked questions

What is CVE-2025-24839?: Mattermost versions 10.5.x <= 10.5.1, 10.4.x <= 10.4.3, 9.11.x <= 9.11.9 fail to prevent Wrangler posts from triggering AI responses. This vulnerability allows users without access to the AI bot to activate it by attaching the activate_ai override property to a post via the Wrangler plugin, provided both the AI and Wrangler plugins are enabled.
How severe is CVE-2025-24839?: CVE-2025-24839 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-24839 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-24839?: CVE-2025-24839 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-24839?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-24839 have an EU (EUVD) identifier?: Yes. CVE-2025-24839 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11360.
When was CVE-2025-24839 published?: CVE-2025-24839 was published on 2025-04-16 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

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